PDFCrack multi-core and multi-computer extension

PDFCrack is a tool to recover lost passwords from a PDF File. The
project is open source (GPL) and publicly available under sourceforge. The tool is written for GNU/Linux
systems and has shown to run under MAC OS X and Windows as well. Download the
sourcefiles (for Linux/MAC OS X/cygwin) and the executable for windows below.

Multi-core extension (multiple threads)

If you have a quad core and want to run pdfcrack on three cores (i.e. 3 threads)
start pdfcrack with:

pdfcrack -t3 pdffile

Note: The multi-core extension only works for user-password
recovery (not the owner password).Note2: For 40-bit encoded PDF files, the password search on multiple
cores does not scale for more than two threads. The underlying cause is that the
password generation (which is mutexed for all threads) takes substantial time in
comparison with the password check. If you want to use more than two cores, you could
start multiple instances of pdfcrack with different password zones (see blow).

Multi-computer extension (password zones)

The additional "-z
currentZone/nrOfZones" parameter allows to start multiple instances of the program on
multiple machines. You can also start multiple instances of pdfcrack on one machine
instead of using the multi-core extension (see above). If you have a cluster of three
machines you can start pdfcrack with:

PC1: pdfcrack -z 1/3 pdffile

PC2: pdfcrack -z 2/3 pdffile

PC3: pdfcrack -z 3/3 pdffile

Note: Password zones do not work with password lists. If you
want to work with passwords list, split the password list first.

Periodic saving of the progress

The progress of the password search is
periodically saved (every 30s) in the file "savestateperiodic.sav". Use this file to
recover the password search after a system crash.

pdfcrack -l savestateperiodic pdffile

Note: As with the original PDFCrack implementation, the
progress is saved in the file "savestatecrash.sav", if pdfcrack is aborted (e.g.
ctrl-c).

Download

Source files

Compile first (call make). On Windows, use cygwin.
Download source files
Fixed Makefile if you have compilations errors (thanks to Kyrill Detinov)

Precompiled for Windows

Thanks to cygwin the pdfcrack can be compiled for
Windows as well. There is no graphical user interface (GUI): use
command prompt (cmd.exe).
Download zip file with
precompiled binary (exe)

Wordlist

There are various wordlists available online. Just take your
favourite search engine and look for "password lists". A good starting point
is the openwall project
.